Movable-window safety device

ABSTRACT

A movable-window safety device for arresting upward movement of a power-driven window glass in a motor vehicle body in the event of obstruction in the window opening comprises a resilient channel for receiving the window glass and which is mounted in a rigid window frame. The base of the resilient channel comprises an electrical detecting member housed in a hollow chamber. The side walls of the resilient channel extend proud of the sides of the rigid window frame and carry curved-over outer lips and inner lips. An obstruction in the window opening is carried upwardly by the window glass and applies a force to one or other of the side walls of the resilient channel, according to whether the obstruction extends inwardly or outwardly of the window opening. The resultant force is applied to the detecting member. The detecting member may be part of a capacitor in the tuned circuit of an oscillator whose frequency correspondingly varies in response to the resultant movement of the detecting member and is detected to arrest the window glass. Instead, it could be a member whose electrical resistance is changed by the applied force and is detected by an appropriate detecting circuit to arrest the window glass. An additional hollow chamber is provided in the base of the channel to increase its resilience.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a movable-window safety device for detectingthe presence of an obstruction in an opening closable by a power-drivenwindow glass, comprising resilient material forming a resilient channelfor mounting in a rigid window frame and for receiving an edge of themoving window glass when so mounted, the resilient channel beingdimensioned so that its two side walls have extensions beyond the rigidwindow frame whereby an obstruction entering the window opening fromeither side thereof is moved into contact with a respective one of theextensions by the moving window glass and applies a force through theextension to the respective side wall and directed towards the base ofthe resilient channel, electrical detecting means mounted within andextending along the rigid window frame so as to be acted on by the saidforce and to produce a corresponding electrical signal, the width of theelectrical detecting means extending substantially across the width ofthe resilient channel so as to respond to the said force applied througheither of the extensions, and control means responsive to the electricalsignal to arrest power-driven movement of the window glass.

2. Description of the Related Art

One such device is shown in FR-A-1 549 640 (corresponding to GB-A-1 98439). In one form of this known device, the resilient channel is mountedwithin an additional rigid channel made of electrically conductivematerial. The combination of this rigid channel and the resilientchannel is mounted within the rigid window frame by means of rubberbuffers which allow the combination to be moved against the resilienceof the rubber buffers by the force produced by an obstruction so thatthe rigid channel moves into contact with another conductor alsoresiliently supported from the window frame. Such an arrangementcomprises a multitude of separate parts and, accordingly, its assemblywould be difficult. In another form of this known device, the outside ofthe base of the resilient channel carries an electrical conductor whichis moved by the force caused by an obstruction into contact with therigid window frame. In this case, the conductor cannot be completelysealed from the surrounding air because the resilient channel must besufficiently free to slide within the rigid window frame.

EP-A-0 648 628 describes movable-window safety devices in which aconductor forming one plate of a capacitor in an electrical oscillatingcircuit is embedded in part of a window channel, or a part associatedwith a window channel, so as to detect the presence of an obstruction inthe window opening by non-contact means--the obstruction altering thefrequency of the oscillator. However, with such non-contact methods itis difficult to ensure reliable operation over a long period of time andin a variety of different ambient conditions. In another form described,the conductor is embedded in a lip extending externally from a windowchannel so as to be physically moved by direct contact between the lipand an obstruction on one side of the window opening. However, such anarrangement is not effective in detecting obstructions approaching fromeither side of the window opening.

SUMMARY OF THE INVENTION

According to the invention, there is provided a movable-window safetydevice for detecting a presence of an obstruction in a window openingclosable by a power-driven window glass, comprising resilient materialforming a resilient channel for mounting in a rigid window frame and forreceiving an edge of the window glass when so mounted, the resilientchannel having a base, a mouth and two side walls and being dimensionedso that the two side walls have extensions beyond the rigid window framewhereby an obstruction entering the window opening from either sidethereof is moved into contact with a respective one of the extensions bythe window glass when the window glass is moving and applies a forcethrough said one extension to the respective side wall and directedtowards the base of the resilient channel, electrical detecting meansmounted within and extending along the rigid window frame so as to beacted on by the force and to produce a corresponding electrical signal,the width of the electrical detecting means extending substantiallyacross the width of the resilient channel so as to respond to the forceapplied through either of the extensions, control means responsive tothe electrical signal to arrest power-driven movement of the windowglass, the electrical detecting means being mounted within a resilientenclosure in the base of the resilient channel, and wherein theresilient material forming the base of the channel is provided with atleast one hollow chamber to increase its resilience, this hollow chamberbeing additional to the resilient enclosure in which is mounted theelectrical detecting means.

In this way, therefore, the electrical detecting means is sealinglyincorporated within the resilient channel, and it and the resilientchannel can be assembled into the window frame as a unit.

BRIEF DESCRIPTION OF THE DRAWINGS

Movable-window safety devices embodying the invention will now bedescribed, by way of example only, with reference to the accompanyingdiagrammatic drawings in which:

FIG. 1 is a perspective view of a motor vehicle showing where the safetydevices can be mounted;

FIG. 2 is a cross-section on the line II--II of FIG. 1, showing one ofthe safety devices mounted in position and in use;

FIG. 3 is a perspective cross-sectional view, corresponding to FIG. 2,of one of the safety devices before completion of its manufacture;

FIG. 4 is a circuit diagram of one form of circuit which can be used ina system in which the safety devices may be used;

FIG. 5 corresponds to FIG. 4 but shows a modified form of the circuitdiagram; and

FIG. 6 corresponds to FIG. 2 but shows a modified form of the devicethereof.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a motor vehicle 5. Each door 6 carries a window frame 8 inwhich a window glass is upwardly and downwardly slidable, the windowglass being raised and lowered by means of an electric motor mounted inthe lower part of the door. For safety reasons, it is necessary toarrange for the upward movement of the window glass to be stoppedautomatically if an obstruction is detected in the window opening.

FIG. 2 shows a safety device embodying the invention which is used, in amanner to be explained, for stopping upward movement of the window glassin the event of detection of such an obstruction.

The safety device 12 is in the form of a window guiding and sealingstrip. The strip 12 comprises generally channel-shaped extruded plasticsor rubber material 14 defining a channel 16 having walls 17 and 18. Thestrip 12 is mounted in the rigid window frame 8 mounted in the upperpart of the door 6.

The material 14 defines integral lips 20 and 22 which together bridgeacross the mouth of the channel 16. The base 24 of the channel isrelatively thick and defines two longitudinally extending hollowchambers 26 and 28. In addition, a web 30 extends across the base of thechannel and defines with it an enlarged chamber 32.

The sides of the base 24 are integrally extended to provide lips 34 and36.

The distal ends of the walls 17,18 of the channel are provided withoutwardly extending lips 38 and 40.

The strip 12 is sized to fit within the U-shape of the window frame 8and is arranged to be a resilient push-fit. When placed in position, itslips 34 and 36 expand outwardly behind shoulders formed where the edgesof the inner and outer door panels 42 and 44 are bent over, and welded,to produce the window frame 8. In this way, the strip 12 is held firmlyin position.

The walls 17,18 of the strip 12 are sized so that their distal edgesextend outwardly of the frame 8, the outer lips 38 and 40 curving overto engage over the edges of the window frame. In this way, gaps A and Bare formed under the lips 38 and 40 for a purpose to be described. Asshown in FIG. 2, the lip 38 may clamp part of the interior trim 41 tothe edge of the window frame.

Inside the chamber 32, a detecting member 50 is positioned. The member50 is inserted into the chamber 32 endwise during manufacture.

The member 50 may take several different forms, as will be described inmore detail below. In one form, it comprises an electrical conductor. Inanother form, it comprises material whose electrical resistance changesin response to applied force or pressure.

The safety device or strip 12 is mounted along the upper part of thewindow frame 8 as shown in FIG. 1 and may also extend down the "A"pillar of the vehicle. Along the "B" pillar of the vehicle, a normalwindow channel may be provided.

FIG. 2 shows the window glass 52. During normal unobstructed movement,it is raised by an electric motor under control of an occupant of thevehicle. As it completes its upward movement, it enters the channel 16,and, in so doing, is sealingly contacted on each side by the lips 20 and22. Advantageously, these lips are covered with flock 54 or othersuitable low friction material.

If an obstruction is present within the window opening, however, such asa human hand, this will be carried upwardly by the rising window glass52 and will make contact with the outer face C or D of the windowchannel, depending on whether the obstruction is presented from insideor outside of the vehicle (or may make contact with both faces C and D).As the obstruction continues to be driven upwardly by the rising windowglass 52, a force will be applied to the face C and/or the face D in thedirection of the arrows F. This force will be transmitted to thedetecting member 50 by the corresponding wall or walls 17,18 of thestrip 12, this process being aided by the gaps A and B and by thechambers 26 and 28 in the base 24 of the strip which provide addedcompressibility for the base.

In a manner to be described, the member 50 detects the presence of theobstruction and abruptly stops upward movement of the window glass.Advantageously, the upward movement of the window glass is not onlystopped but reversed so that the obstruction can be removed.

FIG. 4 shows one form of circuit which may be used for driving thewindow glass 52 up and down and for responding to detection of anobstruction by the detecting member 50. In this case, it is assumed thatthe detecting member 50 comprises an electrical conductor.

As shown in FIG. 4, the circuit comprises a control unit 70 which issupplied with electrical power on lines 72 and 74 from the vehicle'sbattery 76. The control unit 70 includes an oscillator 78 having a tunedcircuit, part of which is formed by a capacitor of which the detectingmember 50 of FIG. 2 forms one plate, the adjacent window frame 8 formingthe other plate. A connection 80 (FIG. 4) is therefore made from theoscillator to the detecting member 50. It will be understood that theextruded plastics or rubber material 14 electrically insulates thedetecting member 50 from the vehicle bodywork.

FIG. 4 also shows the circuit for energising the electrical motor 84 forraising and lowering the window glass 52, this motor being positioned inthe lower part of the door 6 (FIG. 1). The motor 84 is energised bymeans of an "up" switch 86 which is positioned for use by the driver orpassenger. When switch 86 is closed, motor 84 is electrically energisedthrough a further switch 88 forming part of the control unit 70. Switch88 is normally closed. Closure of switch 86 therefore energises motor84, and the window glass 52 thus begins to move upwardly.

A second switch 90 is provided for the driver or passenger, and is usedfor causing the motor 84 to lower the window glass.

In operation, the presence of an obstruction in the window openingcauses a force F to be applied to one or both side walls 17,18 of thestrip 12 in the manner explained. This results in corresponding movementof the detecting member 50. This causes a consequent and significantchange in the capacitance in the tuned circuit of the oscillator 78. Anabrupt and significant change in the oscillator frequency will thereforetake place and this will be detected by a detecting unit 92 (FIG. 4) inthe control unit 70. Detecting unit 92 produces an output which opensswitch 88, thus immediately stopping the motor 84 and the rising windowglass 52. In addition, the control unit 70 may incorporate a reversingunit 96 which responds to the output from the detector 92 by providingan output on a line 98 which reverses the motor 84, so as to cause it tolower the window.

A control 94 may be provided for adjusting the oscillator 78.

When the window glass 52 rises in an unobstructed manner, it will ofcourse eventually reach the base of the channel 16. The limit of itsupward movement will be detected by a conventional limit switch (notshown) which will switch off the motor 84 in the normal way. In itsfinal upward position, the window glass will apply pressure to the baseof the channel, thus moving and/or applying pressure to the detectingmember so. However, the normal limit switch can be used to prevent thecontrol unit 70 (FIG. 4) from responding to such movement of or pressureon the detecting member 50.

In another embodiment, detecting member 50 is not a simple electricalconductor but is instead made of material whose electrical resistancechanges with applied force or pressure. FIG. 5 shows a modified versionof the circuit of FIG. 4 which may be used when the detecting member 50has this form. Items in FIG. 5 corresponding to those in FIG. 4 aresimilarly referenced.

As shown, the circuit of FIG. 5 incorporates a control unit 70A. Thisincludes an output unit 100 which is energised by the battery 76 andapplies an appropriate electrical potential across the member 50 (FIG. 2) by output lines 102 and 104. A detecting unit 92A is connected tolines 102 and 104 and detects any change in electrical resistance of themember 50, caused by applied force (that is, by the force F resultingfrom the presence of any obstruction, as explained above in connectionwith FIG. 2). In the event of detection of such change in resistance,the detecting unit 92A opens switch 88 which thus abruptly stops motor84 in the manner already explained. Again, the control unit 70A may beprovided with a reversing unit 96.

It will be appreciated that the circuits shown in FIGS. 4 and 5 aremerely examples of many different forms of circuit which can be used forresponding to the output of the detecting member 50.

The arrangement of FIG. 6 (in which parts corresponding to those in FIG.2 are similarly referenced) differs from that in FIG. 2 in that thechambers 26,28 are provided on the opposite side of the member 50 ascompared with FIG. 2. In addition, member 50 is a closer fit in itsenclosure 32 than in FIG. 2.

In both the arrangements (FIGS. 2 and 6), different parts of theextruded plastics or rubber material 14 may be given differenthardnesses to suit their respective purposes The material of the base ofthe channel may be relatively soft, for example.

The devices illustrated is advantageous in that it can detect anobstruction which enters the window opening either from the inside orthe outside of the vehicle.

What is claimed is:
 1. A movable-window safety device for detecting apresence of an obstruction in a window opening closable by apower-driven window glass, comprising resilient material forming aresilient channel for mounting in a rigid window frame and for receivingan edge of the window glass when so mounted, the resilient channelhaving a base, a mouth and two side walls and being dimensioned so thatthe two side walls have extensions beyond the rigid window frame wherebyan obstruction entering the window opening from either side thereof ismoved into contact with a respective one of the extensions by the windowglass when the window glass is power-drivingly moving and applies aforce through said one extension to the respective side wall anddirected towards the base of the resilient channel, electrical detectingmeans mounted within and extending along the rigid window frame so as tobe acted on by the force and to produce a corresponding electricalsignal, the width of the electrical detecting means extendingsubstantially across the width of the resilient channel so as to respondto the force applied through either of the extensions, control meansresponsive to the electrical signal to arrest power-driven movement ofthe window glass, the electrical detecting means being mounted within aresilient enclosure in the base of the resilient channel, and whereinthe resilient material forming the base of the channel is provided withat least one hollow chamber to increase its resilience, this hollowchamber being additional to the resilient enclosure in which is mountedthe electrical detecting means.
 2. A device according to claim 1,wherein each extension is formed by the edge of the respective one ofthe walls of the resilient channel.
 3. A device according to claim 2,wherein each edge carries an integral lip extending away from the mouthof the channel and for partially embracing an adjacent part of thewindow frame.
 4. A device according to claim 3, wherein each edgecarries an integral lip for making sealing contact with an edge of thewindow glass.
 5. A device according to claim 1, wherein the hollowchamber is closer to the outside of the base of the channel than theelectrical detecting means.
 6. A device according to claim 1, whereinthe hollow chamber is closer to the inside of the base of the channelthan the electrical detecting means.
 7. A device according to claim 1,wherein the base of the channel is formed with integral lips extendingexternally of the channel and outwardly from the base thereof to makelocking contact with respective formations on the rigid frame.
 8. Adevice according to claim 1, wherein the control means comprises anelectrical oscillator having a tuned circuit for determining thefrequency of the oscillator, and in that the detecting means comprisesan electrical conductor the movement of which in response to the forceaffects capacitance within the tuned circuit and thus the frequency ofthe oscillator, the control means including means responsive tovariation in the frequency of the oscillator to produce a controlledoutput, and means responsive to the controlled output for arresting themovement of the power-driven window glass.
 9. A device according toclaim 8, and including means responsive to the controlled output forreversing the power-driven window glass so as to drive it away from theresilient channel.
 10. A device according to claim 1, wherein thedetecting means comprises material having an electrical resistance thatundergoes a variation in response to the force, and in that the controlmeans comprises means connected to the detecting means for detecting thevariation in its electrical resistance and for producing a controlledoutput, and means responsive to the controlled output for arresting thepower-driven window glass.
 11. A device according to claim 10, andincluding means responsive to the controlled output for reversing thepower-driven window glass so as to drive it away from the resilientchannel.